AU618153B2 - Packaging cylindrical articles - Google Patents

Description

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618153 COMMONWEALTII OF AUSTRALIA PATENTS ACT 19)52 Form COMPLETE SPECIFICATION

(ORIGINAL)

ron oFFICE USE Class Int. Class Application Number: Lodge'd: Complete Specification-Lodged: Accepted: Published: Priozity: 0 9

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flelated Art., TO BE COMPLETED BY APPLICANT 00 Name of Applicant: JOHN LYSAGHT (AUSTRALIA) LIMITED 440

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Address of Applicant: 55 Sussex Street, Sydney, New South Wales, Australia Actual Inventor: RICHARP. HIENRY KENTWELL 0* I Address for Service: SMITH S1IE!"LSTON BEADLB Suite 8, 207 Great North Ro'~d FIVE DOCK NSW 2046 Complete Specification for the lnveriwb entitled: "PACKAGING CYLINDRICAL ARTICLES" J C 0 t 0. 1 2/ 3 I The following -statement is a full description of this invention, including the best method of performing it known to me:- Complete after provisional PJ '1813 dt~ted 6 December 1988 ~L

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~3 1 P/00/01 1 Regulation 3.2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT o Invention Title: PACKAGING CYLINDRICAL ARTICLES The following statement is a full description of this invention, including the best method of performing it known to the Applicant:was This invention relates to thq packaging of cylindrical articles. It was devised for use in the packaging of coils of steel strip for delivery from a process line direct to customers, and is described primarily in relation to that usage hereinafter; but it will be appreciated that the invention is applicable to the packaging of coiled strip materials and like cylindrical articles generally.

Customarily, coils of steel strip are packaged by applying end caps to the coil to cover its circular end faces anid a steel sheet or other wrapper to cover its curved cylindrical surface. E'toh end cap is in the nature of a shallow polygonal pan comprising a polygonal fioor with a rim of upstanding slightly overlapping flanges. If the coil is to be stored or transporled with its axis upright it is stood on end in one such end or transported with its axis upright it is stood on end in one such end i _1 _i 2 cap, the w-apper is applied over the coil and that end cap's rim flanges and a second end cap is applied (as an inverted pan) to the top of the coil with its rim flanges outside and overlapping the top edge of the wrapper. The two end caps and the wrapper are then secured with tensioned straps.

According to present practice the end caps are usually made by hand. This is because the outer diameters of the vary from coil to coil, depending on production parameters and individual customer's requirements for each delivery, so that press forming or drawing of the 10 end caps is impracticable.

o Briefly stated, an operator, working by eye, because of the time constraint compatible with the production of a low cost expendable article, presently takes a circular, sheet steel blank of diameter a somewhat larger than that of the coil to be packaged, applies the blank more or less centrally to an end of the coil and beats the projecting edge margin of the blank sufficiently to crease the blank at the periphery of the coil's end face. The operator then makes a plurality of more or less •equally spaced apart radially extending cuts from the perimeter of the blank to the crease and then beats the tongues so formed down or up, as the case may be, about the curved surface of the coil or the wrapper thereon. The resultant end cap leaves something to be desired in the regularity of its shape and overall neatness, its somewhat irregular and sharp edges are a hazard to the operator when handling the cap and the resultant package doesn't provide really good protection against ingress of rain or dirt because of the segmented nature of the end caps' rim flanges.

to 'r k 4 4 4 44444 4,4 4*4 00444 *4 4 It is believed that circular pans with continuous rim flanges have been produced hitherto by a metal spinning process, but this requires the services of a skilled tradesman and would be unacceptably expensive for the manufacture of package end caps of the kind in question.

It is a!so believed that small paper dishes with pleated rim flanges have been made for cookery purposes, but these are pressed from paper blanks to a standard size or a small range of sizes.

10 An object of the present invention is to provide a method of making metal package end caps which produces circular caps with continuous rim flanges, requires little judgement or skill on the part of the operator, enables individual sizing of the caps to suit the article size and is generally less laborious, time-consuming and hazardous than the 15 present practice.

The invention consists in a method of making a package end cap of a required diameter comprising the steps of forming or selecting a circular metal blank having a diameter in excess of said required diameter, roll forming a peripheral margin of said blank having a width substantially equal to half the amount by which the blank diameter exceeds said required diameter to produce a continuous wave formation therearound, said wave formation having radially extending crest lines, and folding the roll formed margin about its junction with the central portion of the blank it surrounds until the crest lines of said wave formation are substantially perpendicular to said central portion; said wave formation having an amplitude which progressively increases from substantially zero at said junction to a maximum at the free edge of said S margin.

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*4* *04 In practice, the steps of roll forming and folding are efferted more or less simultaneously. The progressive increase in the amplitude of the wave formation causes a corresponding progressive decrease in the length of the longitudinal axis of the formation, that is to say in t;;e circumferences of successive annular elements of the edge margin.

Ideally this equates the effective circumferential length of every such element to the required cap diameter and enables the blank to be converted into a distortion-free, circular pan with a flat floor and a wavy or pleated continuous rim flange.

Due to its continuous nature, the rim flange enables a package to be made which effectively excludes water, while at the same time, due to its pleated nature, the flange admits air between itself and the wrapper to minimise condensation within the package.

The invention also consists in apparatus for putting the method of the invention into effect comprising turn table means to support a circular, sheet metal blank and permit it to rotate about its own axis, at least one pair of co-acting wave forming rolls, and support means for said rolls enabling them to be separated to receive an edge margin of the blank between them and then brought together to nip that edge margin; said support means being such that the axes of rotation of the rolls are inclined or inclinable relative to the plane of the blank and lie in a plane perpendicular to the plane of the blank, and said rolls being such that when rotated they form a wave formation in said margin of an amplitude which increases progressively from substantially zero at the junction of the margin and the centre portion of the blank it surrounds to a maximum at the free edge of the margin.

R 1 r i The wave forming rolls, which are driven in synchronism, may be analogous to straight cut spur gears but of a simple star shaped crosssection. In this instance only the crests of the teeth of the rolls may contact the blank and the wave formation produced is a saw tooth or triangular wave. One or both of such rolls may be tapered so that the teeth on each project progressively further into the initer-tooth spaces of the other to produce the requisite variation of wave amplitude.

Alternatively two untapered rolls may be used with slightly convergent axes of rotation. Then again, if desired for appearance's sake, specially 10 shaped, tapered, close fitting rolls may be used to produce smoothly curved waves with arcuate or possibly sinusoidal half wave shapes.

By way of example, an embodiment of the above described *444 *invention is described in more detail hereinafter with reference to the accompanying drawings.

15 Figure 1 is a side elevation of an apparatus for making a package end cap according to the invention, with some of the nearer parts cut away to reveal more central components more clearly.

Figure 2 is a sectional elevation taken on line 2-2 of figure 1.

Figure 3 is a side elevation of a wave forming roll assembly, being a portion of the apparatus of figure 1 drawn to a larger scale.

Figure 4 is a plan view of the assembly of figure 3.

Figure 5 is a rear elevation of the assembly of figure 3.

'-apu3-~ i- i too: 0 *00 t I o 0 *40440 6 Figure 6 is a perspective view of an end cap according to the invention shown applied to a coil of steel strip Shown in ghost outline.

Figure 7 is a plan view of the cap of figure 6.

Figure 8 is a partly sectioned side elevation of the cap of figure 6.

Figure 9 is an enlarged detail view of the subject matter within the enclosure marked 9 of figure 8.

Figures 10 and 11 are enlarged sectional views taken on lines and 11 respectively of figure 9.

Figure 12 is a perspective diagram showing the roll forming of a 10 blank by star sectioned wave forming rolls, being components of the assembly of figure 3.

Figure 13 is an axial section of the rolls of figure 12.

The illustrated apparatus comprises a stationary part 14 and a mobile part The stationary part 14 comprises substantial steel columns 16, a cross-beam 17, a pedestal 18, rails 19 and turntable means comprising a freely rotatable turntable centre 20, a freely rotatable clamp head 21 (which may be identical to the centre 20, but inverted) and a hydraulic thrustor 22. The arrangement is such that a circular sheet steel blank 24 (see figure 12) may be positioned with its centre point contacting the centre point of the turntable centre 20, and the thrustor 22 Imay then be extended to bring the clamp head 21 into pressure contact -s' j1 I

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*4t* 4040 *444 .4440 44*s 4*4 7 with the blank 24. The blank 24 is then frictionally restrained from any bodily movement other than rotation about its own central axis 25, which is coincident with the common axis of rotation of the centre 20 and clamp head 21.

The mobile part 16 of the apparatus comprises a rigid, fabricated steel, four legged carriage 26 with track wheels 27 adapted to ride on the rails 19 and a flat top plate 28.

The plate 28 is able slidingly to support the major part of the blank 24 when gripped between the centre 20 and clamp head 21 as aforesaid. The plate 28 is slotted to provide access to the blank for the centre 20 and clamp head 21 and the slot extends therefrom to an edge of the plate 28 adjacent a wave forming roll assembly 29. Thus, once the blank 24 has been clamped to the centre 20 the carriage 26 may be advanced along the rails 19 to bring an edge margin 24A of the 15 blank 24 into working engagement with the assembly 29 for roll forming a wave formation in that margin, as will be described more fully below.

When the carriage 26 has been positioned to suit the required cap diameter (by adjusting the width of the edge margin 24A to be roll formed having regard to the selected blank diameter) it may be locked in position by means of a clamping screw 30 which may be tightened against the reaction from an abutment 31 against which a member of the carriage 26 may otherwise slide.

The wave forming roll assembly 29 comprises a rigid fabricated steel chassis 32 upon which the operative components of the assembly are mounted. The chassis 32 is rgidly secured to a cross-member 33 S extending from one side of the carriage 26 to the other. The cross- 1L%

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g; 9, r 8 member 33 terminates at each end in upstanding i,;gs 34 (see figure 1) which in turn are pivotally mounted to extensions of two of the legs of the carriage 26, to enable the entire assembly 29 to swing about an axis lying substantially in the plane of the top surface of the top plate 28.

The swing movement of the assembly 29 may be effected by a hydraulic thrustor 35 extending between cantilevers 36 and 37 projecting from the carriage 26 and chassis 32 respectively. As may be seen from figure 1, which shows the assembly 29 in each of its extreme positions, it can be swung from a substantially horizontal position to a substantially *4 10 vertical position and can also be held in any desired intermediate S- position.

#44 ~The roll assembly 29 further comprises a controllable speed hydraulic motor 38 secured to a bracket 39 with its output shaft coupled to a drive shaft 40 extending through a stationary bearing block 41. A S. 15 driving spur gear 42 and a star sectioned, parallel sided, wave forming roll 43 are keyed to the shaft A second, movable bearing block 44 supports a driven shaft 45 on which a driven spur gear 46 and a second, star sectioned, tapered wave forming roll 47 are keyed (in figures 12 and 13 the degree of taper of roll 47 is exaggerated).

The movable bearing block 44 is welded to and carried by two levers 48 fulcrummed by pins 49 on arms 50 projecting rigidly from the fixed bearing block 41. The levers 48 are connected by cross-tie 51 and a hydraulic thrustor 52 extends from that tie to a pin 53 extending between abutments 54 projecting from the cross-member 33. Thus retraction of the thrustor 52 swings the levers 48 on their fulcrums and 9 lifts the movable bearing block 44 away from block 41 to disengage the gears 42 and 46 and separate the rolls 43 and 47. Provided the assembly 29 is in its lowest or horizontal position, this enables the carriage 26 to be moved to bring the edge margin 24A of the blank 24 between the rolls 43 and 47 to the desired extent. Thereafter, the thrustor 52 may be extended to swing the levers 48 in the opposite direction and bring the rolls 43 and 47 together so that the crests 43A and 47A (figure 13) of their then intermeshing teeth come into forceful engagement with the blank edge margin 24A to form a single wave form 10 or pleat therein.

The thrustor 35 may then be extended to bring the assembly 29 *0 0 to, say, an intermediate position of about 45) inclination. The motor 38 may then be energised to cause the rolls to rotate, so causing the blank 24 to rotate to pass the edge margin 24A between the rolls and at S 15 least partly form a wave formation extending therearound. After one full revolution of the blank 24 the motor 38 may be stopped and the thrustor 35 further extended to bring the assembly 29 into the vertical position. Once again the motor 38 is energised, this time preferably in S the opposite direction, to re-roll the wave formation and produce a fully shaped end cap 55 comprising a central pan floor 56 and a continuous wavy rim flange 57.

It will be seen from figures 9, 10 and 11 that the taper of the roll 47 causes the amplitude of the wave form to increase from substantially zero at the junction 58 of the pan floor 56 and rim flange 57 to a maximum at the free edge of the flange, whereas the wave length remains constant throughout.

r The precise inter-penetration of the teeth of the rolls may be adjustably set by means of abutment screws 59.

It will also be seen that the crests 59 of the waves, being those produc>; by contact with the crests of the teeth of the parallel sided roll 43, are substantially perpendicular to the plane of the pan floor 56.

That is to say the whole of the wave form is positioned outside the inner diameter of the rim flange, thereby producing a neat fitting rim flange of constant inner diameter to suit the outer diameter of the coil or other article to be covered.

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a a a a. a *r a sn *50e In other embodiments of the invention both rolls may be tapered, in which event the final pass of the edge margin 57 through the rolls may be made with the assembly 29 just short of the vertical position, to compensate for the taper of the roll corresponding to roll 43 and achieve the same effect, It will be apparent that in the embodiment of the invention now being described the constancy of the projecting length of the rim flange in the finished cap depends on the accuracy with which the centre point of the circular blank is registered with the axis of rotation of the turntable centre.

This requires care on the part of the operator and, to eliminate that requirement, other embodiments of the invention may provide a three-jawed chuck device, for example with its jaws projecting through radiating slots in the top plate 28, to centre the blank automatically.

In still other embodiments an over-size, not necessarily circular, blank is clamped approximately in place and trimmed to a circle by a c~ i-11 _i r -i I~ 1 i 44,,

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9 04 t 4 o *4i .1 .4 0* 4 44 90,.4 0 11 stationary cutting device as the blank is rotated, thereby to trim the blank to size and leave it accurately centred on the a: of the turntable centre. Alternatively, but less preferably, the blank may be trimmed to a circle by a movable cutting device which is itself accurately centred on the axis of the turntable centre.

As described the roll forming is effected in two passes, one with the rolls inclined at about 450 and the other with them substantially vertical or nearly so.

In other embodiments a single set of wave forming rolls is relied 0 upon to fully form the flange in one pass. That is to say, the set of rolls folds the edge margin through substantially 900 as it forms the wave formation therein.

In still other embodiments two sets of roils spaced apart around the periphery of the blank and operating on synchronised slightly staggered 5 duty cycles may be used. In this instance the rolls first met by the work may be set at 450 and the others vertical. This enables the cap to be fully formed by a single uni-directional operation during which the blank rotates one full turn plus a fraction of a turn equal to the anguiar separation of the two sets of rolls.

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Claims (6)

1. A method of making a package end cap of a required diameter i comprising the steps of forming or selecting a circular metal blank having a diameter in excess of said required diameter, roll forming a peripheral margin of said blank having a width substantially equal to half the amount by which the blank diameter exceeds said required diameter to produce a continuous wave formation therearound, said wave formation having radially extending crest lines, and folding the roll formed margin about its junction with the central portion of the blank it surrounds un, the crest lines of said wave formation are substantially

4-10 perpendicular to said central portion; said wave formation having an amplitude which progressively increases from substantially zero at said j junction to a maximum at the free edge of said margin. 4 2. A method according to claim 1 wherein said steps of roll forming and folding are effected substantially simultaneously. **4*04 4 Ofl. 15 3. A method according to claim 2 wherein said steps of roll forming 4 and folding are effected in a plurality of stages. 4. A method according to any one of the preceding claims wherein the width of said margin is determined by selecting the extent to which the blank is inserted between two wave fotming rolls having converging blank engaging surfaces. Apparatus for effecting the method of any one of the preceding claims comprising turn table means to support a circular, sheet metal blank and permit it to rotate about its own axis, at least one pair of co- acting wave forming rolls, and support means for said rolls enabling 13 them to be separated to receive an edge margin of the blank between them and then brought together to nip that edge margin; said support means being such that the axes of rotation of the rolls are inclined or inclinable relative to the plane of the blank and lie in a plane perpendicular to the plane of the blank and said rolls being such that when rotated they form a wave formation in said margin of an amplitude which increases progressively from substantially zero at the junction of the margin and the centre portion of the blank it surrounds to a maximum at the free edge of the margin.

6. Apparatus according to claim 5 wherein said turn table means comprise a positionally fixed, freely rotatable turntable centre, a freely rotatable clamp head co-axial with said centre and thrustor means adapted to advance the clamp head from a position remote from said f "centre into pressure engagement with a blank lying thereon.

7. Apparatus according to either claim 5 or claim 6 including means for centering said blank on said turn table means. larger sheet supported thereon.

8. Apparatus according to either claim 5 or claim 6 including cutting means to form a circular blank centred on said turn table means from a

9. Apparatus for making a package end cap substantially as described herein with reference to the accompanying drawings. Cw 1 14 A package end cap when made by a method according to any one of claims 1 to 4 or by apparatus according to any one of claims to 9. Dated this twenty-fourth day of September 1991 JOHN LYSAGHT (AUSTRALIA) LIMITED Attorney: r,.BERT G. SHELSTON Fellow Institute of Patent Attorneys of Australia of CARTER SMITH BEADLE 0 64 0 044 0 6 00 0 0 cll LA